$ git clone -n https://src.fedoraproject.org/rpms/bst-external.git /var/lib/mock/f40-build-2283207-55579/root/chroot_tmpdir/scmroot/bst-external
Cloning into '/var/lib/mock/f40-build-2283207-55579/root/chroot_tmpdir/scmroot/bst-external'...
$ git fetch origin d49544e572ed829f3ca72212a8dd330c303ef1b2:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/bst-external
 * [new ref]         d49544e572ed829f3ca72212a8dd330c303ef1b2 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at d49544e Rebuilt for https://fedoraproject.org/wiki/Fedora_40_Mass_Rebuild